The back rank mate is one of the most common tactics in chess. I remember countless occasions when I witnessed one side having a completely won game, being careless, and losing the game by allowing a back rank checkmate.

Let’s start out with a simple example:

Black has just played Ne6-g5 to attack the white queen. Why was this move a big mistake?

Because while this move protects against the checkmate threat of Qxh7, it allows another mate threat of 1.Qc8.

The next example is a bit more complicated. It involves a combination to reach the goal.

Black has just played Rf8-b8 attacking White’s queen. What should be White’s powerful response which results in a two move checkmate?